Digital cameras in recent years, particularly, single-lens reflex cameras adopt a RAW recording mode in which image data that is output from an image pickup element and that is subjected to analog-to-digital conversion is directly recorded on a removable memory, such as a secure digital (SD) card, as a file without performing image processing to the image data. Since the RAW file is not capable of being directly displayed in a display unit after being transferred to an information device, such as a personal computer (PC), the image processing is performed in the information device. A display image file generated by converting the RAW file into a certain file format, such as Joint Photographic Experts Group (JPEG), is displayed in the display unit. Such image processing is generally referred to as development.
The RAW file has the following three features:
1. Since the RAW file is less subject to deterioration in editing, compared with a JPEG image that has been subjected to the development in image capturing and recording, higher image quality is achieved. However, it is necessary to perform the development each time the RAW file is displayed and, thus, there is a problem in that it takes time to process the RAW file.
2. There is a problem in that the RAW file has a file size larger than that of the JPEG file.
3. The RAW file has an image quality adjustment function (hereinafter referred to as a RAW function) that is unavailable for the JPEG file subjected to the development and that is only available for the RAW file before the development.
It is desirable that the JPEG file be normally used when the image is simply viewed from the viewpoint of the features 1 and 2, and that the RAW file be used only when the function specific to the RAW file is used from the viewpoint of the feature 3.
Accordingly, some digital cameras in recent years adopt a RAW+JPEG recording mode in which a RAW file is recorded and at least one JPEG file that is subjected to the development and that is for the same image capturing as that of the RAW file is also simultaneously recorded. In such digital cameras, a set of the RAW file and the JPEG file is transferred to the information device, such as the PC, in the image capturing in the RAW+JPEG recording mode. The information device generally uses the RAW file when the RAW function is used and otherwise uses the JPEG file. RAW data and JPEG data generated from an image signal output from the image pickup element in the same image capturing are hereinafter referred to as simultaneous recording RAW and simultaneous recording JPEG, respectively. In order to realize such a usage, it is necessary to manage the simultaneous recording RAW and the simultaneous recording JPEG in association with each other. PTL 1 discloses a technology to determine whether the simultaneous recording RAW exists in selection of the simultaneous recording JPEG and to disable the RAW function if the simultaneous recording RAW does not exist on the assumption that both the simultaneous recording RAW and the simultaneous recording JPEG exist in the same folder in the same device.
In contrast, new type portable information devices, such as tablets and smartphones, are in widespread use in recent years. Also in such portable information devices, a lot of JPEG files are generally processed with increase in capacity of non-volatile storage media. However, the storage capacities of the portable information devices have not been increased to values appropriate for storage of a lot of RAW files having file sizes larger than those of the JPEG files. Accordingly, it is desirable that the JPEG files be stored in the portable information devices and the RAW files be stored in other devices having larger storage sizes.
However, when the simultaneous recording JPEG and the simultaneous recording RAW are stored in different devices, the RAW function is disabled in the selection of the simultaneous recording JPEG in the related art because the simultaneous recording RAW does not exist in the same device as that of the simultaneous recording JPEG. Accordingly, there is a problem in that a user misunderstands that the RAW function is unavailable even when the simultaneous recording RAW exists in another device.